Rainy Season in West Africa: Navigating Risks for Organizations and Employees

West and Central Africa’s rainy season (May–October) brings flooding, disease outbreaks, and infrastructure failure that directly threaten organizational operations. Here is what the data shows, what the risks are, and what risk managers need to act on now.

Key takeaways

• West and Central Africa’s rainy season is not only a weather event. It is an operational risk that can disrupt staff movement, damage facilities, interrupt supply chains, and limit access to healthcare.
• Risk levels vary significantly by country. Nigeria, Chad, Mali, DRC, and Niger show elevated exposure and/or constrained coping capacity, meaning organizations may need to plan for limited support from local emergency systems.
• Rainy season impacts were lower in some countries in 2025 than in 2024, but that does not mean the overall threat is decreasing. It shows why organizations should plan for country-specific and year-to-year variability rather than relying on the previous season as a guide.
• Organizations should act before the season begins by assessing flood exposure, mapping alternative routes, testing evacuation plans, establishing offline communication protocols, and briefing staff on health risks.

Why rainy season risk requires operational planning

The 2025 season claimed 783 lives, affected 2.4 million people across 17 countries, displaced 394,000 people, and damaged or destroyed 148,000 homes. In Nigeria alone, 403,000 people were affected and 136,000 displaced. 115 health facilities were damaged, limiting the very infrastructure communities depend on when floods strike.

Why existing risk frameworks fall short

The scale of disruption reflects a deeper planning problem. Flood hazards in West and Central Africa remain poorly documented due to persistent data gaps, and contingency plans across the region have consistently underestimated local conditions and struggled to sustain infrastructure over time. Organizations are managing rainy season risk with incomplete information and climate projections suggest the gap between current preparedness and actual exposure will only widen: flood frequency and magnitude in West and Central Africa are expected to increase under both near- and long-term scenarios.

Despite the scale of destruction, 2025 saw lower figures than 2024 in several countries. That does not mean risks are fading. It reflects how climate shocks are becoming increasingly unpredictable; some countries recorded an upward trend, while others saw decreases, all within the same season. For organizations, that variability is itself the risk.

Country risk: flood exposure and response capacity vary significantly

Infrastructure quality and government response capacity differ widely across West and Central Africa. In practice, this means the same flood event can have very different consequences depending on where your people are, how quickly roads get cleared, whether hospitals can absorb additional patients, and how effectively local authorities coordinate a response.

Country-level data from the INFORM Risk Index 2026 on both flood exposure and coping capacity points to where organizations should particularly factor risk into travel and operational decisions.